Stabilized fuel oil compositions



United States Patent 3,340,030 STABILIZED FUEL OIL COMPOSITIONS Gardner E. Gaston, Tarentum, and Edward Mitchell,

Valencia, Pa'., assignors to Gulf Research & Development Company, Pittsburgh, Pa., a corporation of Delaware No Drawing. Filed Mar. 27, 1964, Ser. No. 355,495

5 Claims. (Cl. 44-62) stantial proportion of catalytically cracked oil, such as fuel oil containing at least 20 percent by weight, or more, of catalytically cracked oil blended with straight run distillate.

The combination of addition agents of this invention not only produces a synergistic effect in fuel oil in regard to stabilization of the oil and dispersancy or filterab-ility of the oil, but also produces a synergistic elfect in fuel oil in regard to rapidity of water separation. Furthermore, one'of the agents in thesynergistic mixture of this invention, if it is to be effectively used without the other agent for stabilization purposes, must be present in a concentration range that can seriously retard filtration of the oil, but when this same agent is used as in the synergistic mixture of this invention dispersancy and filterability properties of the fuel oil are substantially improved.

The agents utilized synergistically in fuel oil blends of this invention are (a) alkaline earth salts and/or basic alkaline earth salts of alkyl benzene sulfonic acid and (b) a copolymer of an oil soluble alkyl acrylate ester or alkyl methacrylate ester and a dialkyl aminoethyl acrylate or methacrylate ester.

The salt of the alkyl benzene sulfonic acid or the basic salt of the alkyl benzene sulfonic acid of the synergistic mixture can have the general formula s onion and/or R Ice The copolymer component of the snyergistic mixture is the polymerization product of wherein R is hydrogen or a methyl group, preferably a methyl group; R is an alkyl group containing 8 to 18 carbon atoms in a configuration capable of imparting oil solubility to the copolymer agent; R and R are the same or different alkyl groups containing 1 to 18 carbon atoms each, and preferably containing 1 to 5 carbon atoms each. The copolymer should contain a greater proportion of the non-amino ester, than of the amino ester. Suitable copolymers can be obtained by using between about 2 to percent by weight of the amino ester and between about 98 to 65 percent by weight of the non-amino ester.

Examples of suitable alkyl esters for the formation of the copolymer are octyl acrylate, isodecyl methacrylate, tetradecyl acrylate, isohexadecyl methacrylate, and octadecyl methacrylate. Examples of suitable amino esters for the formation of the copolymer are dimethylaminoethyl acrylate, dipropyl aminoethyl methacrylate, isobutyl, n-butyl-aminoethyl methacrylate, isoamylheptylaminoethyl methacrylate, didodecylaminoethyl acrylate, isotetradecylisohexadecylaminoethyl methacrylate, and dioctadec ylaminoethyl methacrylate.

The synergistic effect of the agents of this invention in regard to stability improvement is apparently a detergent effect since the agents function individually as detergents in the inhibition of sludge formation. The synergistic effect does not appear to be inhibition of oxidation since these agents do not function individually as oxidation inhibitors. The agents of this invention are not soluble in each other and are therefore separately added to the fuel oil. If desired, single phase concentrates containing up to 50 percent by weight of the additives in keroesne can be prepared. The weight ratio of one agent to the other in the fuel oil can generally be between 9:1 and 1:9; is preferably between 7:3 and 3 :7; and most preferably is between 6:4 and 4:6. As is indicated in Table 2 below, the use of more than a very small percentage of the copolymer agent in fuel oils induces severe filter clogging and therefore the copolymer agent is not present in any fuel oil blend of this invention in a proportion greater than 0.05 percent by weight. A suitable range for the coplymer agent is between 0.001 percent and 0.05 percent by weight dissolved in fuel oil. The upper concentration limit for the copolymer agent is preferably no higher than 0.005 or 0.01 percent by weight.

A series of tests was made toillustrate the synergistic effect of the agents of this invention. The synergistic agent utilized in these tests comprised a 1:1 mixture of (a) a mixture of the barium salt and the basic barium salt of alkylbenzene sulfonate, and (b) an /20 weight ratio copolymer of lauryl methacrylate and diethylaminoethyl methacrylate. The results of these tests are shown in Table 1. Y

TABLE 1 B arium Sulionate Plus polymer Barium Sul- Copolymer fonate Alone No Additive Alone Fuel Oil: 1

South Louisiana straight run No. 2 in el oil distillate FCC Light Catalytic Gas Oil Additive, pounds/1,000

barrels:

80/20 copolymer of lauryl methacrylate and diethylaminoethyl methacrylate Mixture of the barium salt and the basic barium salt of alkyl benzene sulfonate Stability Test: Insolubles precipitated out after heating sample for 64 hours at 210 F., milligrams insolubles per 600 grams of sample 1 See the following table:

Inspection data of fuel oil blend As shown in Table 1, the use of pounds per 1000 barrels of the copolymer alone resulted in a precipitate of 73 milligrams per 600 grams of sample; the use of 17.8 pounds per 1000 barrels of the alkylbenzene sulfonate salt alone resulted in a precipitate of 88 milligrams per 600 grams of sample; while the use of pounds per 1000 barrels of a 1: 1 mixture of the same polymer and the same sulfonate salt resulted in a precipitate of only 4 milligrams per 600 grams of sample.

Additional tests were made to further illustrate the synergistic efiect of the agents of this invention in imparting TABLE 2 Fuel Oil Blend of About Equal Proportions of Fluid Catalytically Cracked and Straight Run Distillate Barium Sul- Barium Sulfonate Alone ionate Plus Copolymer Alone Copolymer Additive, pounds/1000 barrels:

/20 copolymer of lauryl methaerylate and 10- 20 15.

diethylaminoethyl methacrylate. Mixture of the barium salt and the basic 53. 5 35. 7. 17. 8 10.

barium salt of alkyl benzene sulfonate. Water Separation Test: 1 Time required for water 5-24-.. 524 5 1 3 3.

go separate from oil and for oil to become clear,

ours. Stability Test: Sample heated for minutes at Stable Stable, bor- Borderline, Stable Borderline, Unstable.

300 F. then filtered through l-inch filter paper derline. unstable. unstable. disk. Precipitate compared with standard disk. Filtration Test: 2

Initial fiow rate, g.p.h 14. 1 7. 3 14. 6 7. 5 Average reduction in permeability, percent. 1 13. 9 77 1 Water Separation Test: 100 ml. of distilled water and 100 ml. of fuel oil are agitated with a copper paddle revolving at 1,550

r.p.m. for 5 minutes at room temperature.

2 Filtration Test: A mixture of the fuel oil with 0.8 percent by volume of aqueous rust slurry (0.4 mg. rust/ml. slurry) and 0.016 percent by volume of synthetic sludge are continuously recirculated through a filter. At the end of each hour contaminants and additives are again added. The test is tenninated when 12 gallons of fuel mixture are filtered or when filter plugging exceeds percent. Permeability is determined by measuring the fiow rate through the filter under a constant head of 1 8 niches oi fuel oil. The initial capacity of the filter is determined with clean fuel and succeeding measurements are made hourly using the contaminated fuel.

Table 2 shows that 20 pounds of the synergistic mixture of this invention in 1000 barrels of fuel oil imparts stability to the oil, while 20 pounds of the copolymer in 1000 barrels of fuel oil results in stability characteristics which are described as being only borderline to unstable, and 17.8 pounds of the barium sulfonate per 1000 barrels of fuel oil also results in stability characteristics which are only borderline to unstable.

Table 2 further shows that a fuel oil containing 20 pounds of the synergistic mixture of this invention required only 1 hour to become clear after admixture with water, while a fuel oil containing 20 pounds of the copolymer alone in 1000 barrels required 3 hours, and a fuel oil containing 17.8 pounds of the barium sulfonate alone in 1000 barrels required 5 hours.

As is shown in Table 2, the use of 20 pounds of the synergistic mixture in 1000 barrels of fuel oil, which introduces about 0.0033 percent by weight of the copolymer into the fuel oil, resulted in only a 9 percent reduction in permeability in the filtration test while 20 :pounds of the copolymer alone in 1000 barrels of fuel oil resulted in a 77 percent reduction in permeability. Any adverse elfect u-pon filtration is a highly disadvantageous characteristic in a fuel oil additive since fuel oils must be filtered prior to being sprayed in oil burners. It is therefore a further advantage of the synergistic mixture of this invention that improved stability, dispersancy and water separation characteristics are imparted to fuel oil with the presence in the fuel oil of only a very small quantity of the polymer component.

We claim:

1. A composition comprising a fuel oil at least 20 percent by weight of which is catalytically cracked; at least one sulfonate salt selected from the group consisting of and R wherein R represents one or more alkyl groups, at least one of which contains 8 to 18 carbon atoms, and M represents an alkaline earth metal; and a copolymer of wherein R is hydrogen or a methyl group, R is an alkyl group containing 8 to 18 carbon atoms, R and R are the same or different alkyl groups containing 1 to 18 carbon atoms each, the amino ester comprising about 2 to 35 percent of the copolymer; the ratio of said sulfonate salt to said copolymer being between about 1:9 and 9: 1; and said copolymer comprising between about 0.001 and 0.05 weight percent of said composition.

2. A composition comprising a fuel oil containing at least 20 percent by weight of catalytically cracked fuel oil blended with straight run fuel oil; at least one sulfonate salts selected from the group consisting of R Mand R wherein R represents one or more alkyl groups, at least one of which contains 8 to 18 carbon atoms, and M represents a metal selected from the group consisting of calcium, barium, magnesium and strontium; and a copolymer of wherein R is an alkyl group containing 8 to 18 carbon atoms, R and R are the same or different alkyl groups containing 1 to v5 carbon atoms each, the amino ester comprising about 2 to 35 percent of the copolymer; the ratio of said sulfonate salt to said copolymer being between about 7:3 and 3:7; and said copolymer comprising between about 0.001 and 0.05 weight percent of said composition.

3. The composition of claim 2 wherein the metal is barium.

4. A composition com-prising a fuel oil containing at least 20 percent by weight of catalytically cracked fuel oil blended with straight run fuel oil; at least one sulfonate salt selected from the group consisting of and R SOQBEOH wherein R represents one or more alkyl groups at least one of which contains 8 to 18 carbon atoms; and a copolymer of wherein R is an alkyl group containing 8 to 18 carbon atoms, R and R are the same or different alkyl groups containing 1 to 5 carbon atoms each, the amino ester comprising about 2 to 35 percent of the copolymer; the ratio of said sulfonate salt to said copolymer being between about 6:4 and 4:6; and said copolymer comprising between about 0.001 and 0.01 weight percent of said composition.

5. A composition comprising a fuel oil containing a major proportion of catalytically cracked fuel oil blended with straight run fuel oil; at least one sulfonate salt selected from the group consisting of oil soluble alkyl benzene barium sulfonates and oil soluble alkyl benzene basic barium sulfonates; and a copolymer of lauryl methacrylate and diethylaminoethyl methacrylate, said amino ester comprising about 20 percent of the copolymer; the ratio of said sulfonate salt to said copolymer being about 1:1; and said copolymer comprising about 0.003 weight percent of said composition.

References Cited UNITED STATES PATENTS 2,626,207 1/1953 Wies et al. 44-71 X 2,737,452 1/1956 Catlin et al 44-71 X DANIEL E. WYMAN, Primary Examiner.

W. J. SHINE, Assistant Examiner. 

1. A COMPOSITION COMPRISING A FUEL OIL AT LEAST 20 PERCENT BY WEIGHT OF WHICH IS CATALYTICALLY CRACKED; AT LEAST ONE SULFONATE SALT SELECTED FROM THE GROUP CONSISTING OF 